Intramolecular Hydrogen Bonding in N-Substituted 2-Chloroadenosines: Evidence from NMR Spectroscopy.

Two forms were found in the NMR spectra of N-substituted 2-chloroadenosines. The proportion of the mini-form was 11-32% of the main form. It was characterized by a separate set of signals in COSY, N-HMBC and other NMR spectra.

Enzymatic Synthesis of 2-Chloropurine Arabinonucleosides with Chiral Amino Acid Amides at the C6 Position and an Evaluation of Antiproliferative Activity In Vitro.

A number of purine arabinosides containing chiral amino acid amides at the C6 position of the purine were synthesized using a transglycosylation reaction with recombinant nucleoside phosphorylases. Arsenolysis of 2-chloropurine ribosides with chiral amino acid amides at C6 was used for the enzymatic synthesis, and the reaction equilibrium shifted towards the synthesis of arabinonucleosides. The synthesized nucleosides were shown to be resistant to the action of adenosine deaminase.

Encouraging Young Pediatric Surgeons and Evaluation of the Effectiveness of a Pediatric Endosurgery Workshop by Self-Assessment and an Objective Skill Validation System.

Japanese pediatric endosurgery experts conducted a workshop for young pediatric surgeons in Russia in collaboration with Russian expert pediatric surgeons. This study was aimed to develop a contributive workshop program and evaluate its impact on young pediatric surgeons. A 2-day pediatric endosurgery workshop was held in Moscow in February 2020.

Synthesis of 2-chloropurine ribosides with chiral amino acid amides at C6 and their evaluation as A adenosine receptor agonists.

A series of purine ribonucleosides bearing chiral amino acid amides at the C6 position of 2-chloropurine was synthesized. Molecular docking of the synthesized analogs of 2-chloroadenosine by their affinity for A adenosine receptors (AARs) was conducted. The investigation of AAR stimulating activity of synthesized nucleosides was carried out in a model of an isolated mouse atrium.